Troughing idler roller assembly for belt conveyors



y 3, 1965 w. N. POUNDSTONE 3,194,387

TROUGHING IDLER ROLLER ASSEMBLY FOR BELT CONVEYORS Original Filed Feb.16, 1960 3 Sheets-Sheet 1 INVENTOR. WILLIAM N. POUNDSTONE .BY S YJMQ 2LA; ATTORNEY y 1955 w. N. POUNDSTONE 3,194,387

TROUGHING IDLER ROLLER ASSEMBLY FOR BELT CONVEYORS Original Filed Feb.16, 1960 3 Sheets-Sheet 2 mvamon WlLLlAM N. POUNDSTONE 5 LL ATTORNEY y13, 1965 w. N. POUNDSTONE. 3,194,387

TROUGHING IDLER ROLLER ASSEMBLY FOR BELT CONVEYORS Original Filed Feb.16, 1960 3 Sheets-Sheet 3 J A I. i I ,1 w. 3 o m9 I .w u i i w O: Om

INVENTOR. WILLIAM N. POUNDSTONE .4; AT T0 RNEY """TID J L ci c UnitedStates Patent 3,194,387 TROUGHING IDLER ROLLER ASSEMBLY FGR BELTCGNVEYORS William N. .loundstone, Morgantown, W. Va., assignor toChristopher Coal Company, Osage, W. Va., a corporation of West VirginiaOriginal application Feb. 16, 1960, Ser. No. 9,077, new Patent No.3,082,860, dated Mar. 26, 1963. Divided and this application Dec. 20,1961, Ser. No. 160,774

2 Claims. (Cl. 198-492) This invention relates to troughing idlerrollers which are utilized to support the troughed conveying reach of anendless conveyor belt, and more particularly to improved idler rollerassemblies for flexible side frame supported belt conveyors.

This is a division of my United States patent application Serial Number9,077 filed on February 16, 1960, now Patent No. 3,082,860 and titledTroughing Idler Roller Assembly for Belt Conveyors.

The conventional endless belt conveyor consists of a belt supported by aseries of idler rollers. The belt is driven by a belt drive means. Thebelt has a troughed conveying reach supported in a generally horizontalmanner by a series of troughing idler rollers. The conveying reachcarries the material to be transported by the conveyor belt. Theconveyor belt has a return reach supported in a generally horizontalmanner, usually below the conveying reach, by a series of return reachidler rollers. The return reach returns the empty portion of the belt tothe belt drive to form a continuous path for the endless conveyor belt.

In recent years belt conveyors have been constructed in which a pair offlexible side frames are trained along a conveying course to support theconveyor belt. The flexiole side frames are usually formed of wire ropeor the like, and are supported at intervals by side frame supportingmeans such as vertical side frame supporting stands. The spaced sideframes extend in a generally parallel manner along the conveying course.Idler rollers span the side frame members to support the conveying reachof a belt conveyor.

Flexible side frame belt conveyors have many advantages which make thempopular in the mining industry. Among these advantages, flexible sideframe conveyors are easily erected and disassembled for movement.Certain types of flexible side frame conveyors also provide an inherentbelt training action which is valuable in belt conveyors. An example ofan improved type of flexible side frame supported belt conveyor may befound in my copending United States patent application Serial No. 690,-684 filed on October 17, 1957.

In flexible side frame supported belt conveyors, the force exerted bythe load on the conveyor belt conveying reach is transferred through thetransversely extending idler rollers which support the conveying reachto the flexible side frames of the conveyor. Since the idler rollers areconnected to the flexible side frames, this transfer of force causes theidler roller assemblies of a flexible side frame supported belt conveyorto react somewhat differently than the idler roller assemblies of rigidside frame supported conveyors as will be discussed in the followingparagraphs.

In most material carrying belt conveyor systems, the conveying reach ofthe belt conveyor is troughed to retain the conveyed material. It isrecognized as desirable to have the trough of the conveying reach deepensomewhat when the load on the conveying reach is increased so that agreater volume of material may then be retained on the belt. In theearly flexible side frame supported conveyor systems, troughing idlerrollers with flexible shaft members were utilized to support the beltconveying reach.

By flexible shaft members are meant both shaft members formed offlexible material such as wire rope and shaft members formed of sectionsof rigid material joined by pivot pins or hinged joints. The term isintended to encompass any shaft member which is not a rigid unit fromend to end. These flexible shafted idler roller assemblies usually hungin approximately a catenary curve between two flexible side framemembers of the conveyor system. As the load on the conveying reach ofthe belt conveyor was increased, the trough of the conveying reachdeepened because the flexible shatter idler rollers permitted thecatenary curve to change shape. The deepening of the rough of theconveying reach was also eflected by the fact that the flexible sideframe members of the conveyor system moved toward each other in thevicinity of the transversely extending idler roller assemblies. Thisinward movement of the flexible side frames of the conveyor system hadthe effect of shortening the span which the flexible shafted rollerassemblies bridged. Although a certain amount of trough deepening underload is desirable, excessive deepening of the troughed conveying reachof the belt conveyor often occurred when the conveying reach of aflexible side frame supported conveyor was heavily loaded.

To overcome the excessive deepening of the trough of the conveyingreach, rigid spreader members were made a part of the troughing idlerroller assemblies that spanned the distance between the generallyparallel flexible side frames of the conveyor system. The idler rollerswere still formed with flexible shafts, but the distance between theflexible side frame members was rigidly fixed at the idler rollerassembly by the spreader members. While the spreader members preventedexcessive deepening of the trough of the conveyor conveying reach, theychanged some of the advantageous characteristics of flexible side frameconveyors.

One of the advantageous characteristics of flexible side frame conveyorswhich was changed by the spreader member was the inherent ability of theflexible side frames to maintain the flexible shafted idler rollerassembly in contact with the belt conveying reach under all conditionsof belt loading. For example, when a flexible shafted idler rollerwithout a rigid spreader member was utilized in a flexible side frameconveyor and when the conveying reach of the belt was lightly loaded,the flexible side frames exerted tension on the flexible shafted idlerroller assembly so that the trough of the idler roller assembly becamemore shallow and the idler roller was maintained in contact with theunder side of the belt throughout the entire width of the belt. When theload on the conveying reach was increased, the trough of the flexibleshafted idler roller assembly deepened by drawing the flexible sideframe members more closely toward each other.

When the spreader member was added to the flexible side frame supportedconveyor system, the distance between the flexible side frame memberswas fixed at the roller assembly. Accordingly, when the conveying reachof the belt was relatively lightly loaded, the conveyor belt conveyingreach tended to flatten so that it rode up out of the trough of theidler roller assembly. In such a situation, only the edges of the beltconveying reach contacted the idler rollers so that there was excessiveconveyor belt wear along the edges of the belt. When the spreadermembers fixed the distance between the flexible side frames, the abilityof the flexible side frame conveyor to maintain the flexible shaftedidler roller in contact with the belt conveying reach throughout thewidth of the belt conveying reach no longer existed.

Another advantage of flexible shafted idler rollers is the fact thatthey may easily be shipped and stored with little danger of shaftdeformation and shaft breakage. Further, the flexible shafted idlerrollers can often be ,URE 4.

r w f3 disassembled into relatively short lengths so that they may moreeasily be shipped andstored.

When it became necessary to utilize spreader members with the flexibleside frame conveyors, this ease of han d-ling characteristic of theidler roller assemblies was often lost; The spreader members were-rigidstructural elements which were long enough to span the distance be tweenthe flexible sideiframe's f the conveyor system.

It became the practice to assemble the idler rollers and the spreadermembers asa unit and not to disassemble them. Accordingly, a spreadermember and an, idler roller, when assembled as a unit, made a bulky,difficult to'handle conveyor system element.

. The present invention contemplates several forms of idler rollerassemblies that provide the aforementioned advantages-of flexibleshafted idler roller assemblies when utilized without spreader membersin the flexible ,side frame supported belt'conveyor systems but whichelimia nate the excessive troughing of the belt conveyor reachthatoriginally initiated the useof rigid spreader meme bers.

- To accomplish these desirable results, the present in- Ventionprovides idler roller assemblies which are completely flexible withinthe normal range of belt conveying reach loading conditions, butwhich'inhibit the excessive troughing of the belt conveying reachwhen'additional loads are placed upon the conveying.reach.,,

A In'operation, the idler roller assemblies of the present inventionpermit deepening of the belt conveyor belt conveying reach trough bypermitting the flexible side frame members of the conveyor system to bedrawn toward each'other as the belt conveying reach load increases.After the flexible side frames move together to within a minim-umdistance of each other, their further movement toward each other isinhibited by the idler .roller construction of the present invention. aWith the foregoing considerationsJin' mind, it is a showing certaindetailsofconstructionrof the individual cylindrical'roller members ofthe embodiment of FIG-T- URE 6.

FIGURE '8 i is an'enlarged sectionalviewtaken along! line 8-8ofFIGUREfif';

a conveying course, a

The troughed conveyingreach. 1690f an endless belt j conveyor ispositioned in' generally parallelrelationto primary object of thepresent invention to provide an improved idler roller assembly.

Another object of this invention is to provide an imframe supported beltconveyor.

Another object of the present invention is llO PIOVldfi an idler rollerassembly for a flexible side frame supported belt conveyor whichproduces the advantages of a flexible.

shafted idler assembly, but which eliminates excessive troughing of thebelt conveying reach.

' Another object of the invention is to provide an idler roller assemblywhich eliminates the requirement for separate, rigid spreader memberswhen utilized withflexiblej'side' frame supported belt conveyors Anotherobject 'of'the present invention is to provide idler roller assemblieswhich may be compactly and safely packed for shipping and storage.

-- These and other objects of this invention will become apparent asthis description proceeds in conjunction .withthe accompanying drawings.

In the drawings:

FIGURE '1 is'an elevational view of one embodiment of the presentinvention.

FIGURE '2 is a fragmentary perspective view on an enlarged scale of theshaft hinge of the embodiment of FIGURE 1.

FIGURE ,3 is a partial elevation on an enlarged scale showing the:relative positions of two of the cylindrical rollers oftthe embodimentof FIGURE 1.

FIGURE 4 islan elevational view, partially in section, showing a secondembodiment of the present invention.

, FIGURE ,S is-a sectionalview on. an enlarged scale showing certaindetails of construction ofthe individual cylindrical roller FIGURE 6 isa sectional elevation of=a third embodiment of the present invention.- a

4:0 proved troughing idler roller assembly for a flexible side 7 theside frame members 12 and 14. and is supported by idler rollerassemblies 10.11

The shaft menibe'riof the idler roller assembly ltiis divided intoshaftmemberxend jsections 18 .and 20, and a shaft membercenter section22.15" The end'sections .18 andyZti-andlthe. centersection 22,;of theshaft -member are-joined by hinges indicated generally at 24.5 The adivision of the shaft member into three sectionsisj by ?v way of exampleonly, and it will be appreciated .that the f 1 shaft member couldbe'di'vided intoa greaternurnber of sections ora lesser number as the.individual requirements ,7

of the particular conveyor system dictate.

Each of the. hingesrz tfiare formed with a pair of angled t.

hinge arms 26secure'd to the shaft?memberend'sections- 18 or 20. Theangled arms 26 are best seen inFIGURE Zand may :be' either formed"integrally'vvith the shaft member end sections 18 or ZOorZrnay beaflixed thereto as by welding. The shaft'membercenter section 22 has ahinge arm 18 secured to'each' of its jendsl The hinge arm 28 may besecured to-theshaft member center; section as by welding or it may beformed integrallyftherewithfr a Each or the hinge arms 26 and 28; has anenlarged portion 30 formed atits end. I The enlarged portions 36 pin 32that is disposed transare bored to receive a hinge versely of the shaftmember.

A pad-34 preferably formed of a deformable resilient, substance such, asrubber, may be secured toftheen'ds of: r the end sections: 18 and 20.and the center section 22 to provide a resilient cushion when'the endsof the respective shaft member sections contacteach other- T h'e-pad3415" not acritical portion of the presentfinvention and may be omittedif desired; "Its" function will become apparent as this descriptionproceeds.

- A rigid cylindricalroller member. 38is rotatably mounted' on'eachiofthe shaftmember sections18,:ZtLfand 22, and supportedltherebyi The rigidcylindricalrollermember's support the troughed conveying reachlo'ftheendless;

belt conveyor;

7 With the foregoing arrangement of. the components of the idler rollerassembly in mind, the operation of the idler.

roller assembly of FIGURES "1-3 in a flexible sidefrarne;

supported conveyor may be considered; The individual sections 18; 20and22 of the shaftgmemberofthe idler; 5 r'oller assembly areconnected byhinge pins 32.' Assclearly shown in FIGURE 1; the hingepins32,"about;which the. sectionspivot relative to eachothensa're oflistfromand 5' disposed below the longitudinal axes of the individual shaftsections 18, 20 and 22; The shaft r'nember end sec-1 tions 18 and?!)have clamps li fisecured to-their outerend portionsto clamp the idlerroller a'ssembfy 10 between the flexible side frame members 12 and 14.

r Withisuc'h a construction, the, individual shaft sections, a

may move relative to each other to-qvary thedepth ofithe trough ofthecbelt conveying reach 16,. However, the

depth of thebelt conveying reach trough may not exceed apredeterminedmaximum.- ,The'maximum depth of the belt conveying reachtrough is-determined by the=angles at which the hingearms26 and 28 areset relativefto the end: sections 18 and 201and the center. section 22respectively. 7

FIGURES land 3 illustrate therelative positions, of the shaft sectionsand cylindrical rollers 33 under two belt loading conditions. In FIGURE1, the belt conveying reach is relatively lightly loaded. The tension inthe flexible side frame members 12 and 14 is sufficient to exert tensionon the idler roller assembly 10. This tension maintains the idler rollerassembly It) in suspension between the flexible side frame members l2and 1 The trough of the belt conveying reach 16 is relatively shallow,and the pads 34 on the ends of the shaft end sections 13 and 2t) and theshaft center section 22 are are maintained out of contact with eachother by the tension exerted on the idler roller assembly 10.

In FIGURE 3 the solid lines of the shaft sections 20 and 22 and thecylindrical roller members 38 represent the relative positions of thesecomponents when the conveyor belt conveying reach is relatively lightlyloaded as shown in FIGURE 1. The phantom line positions of shaft 29 andcylindrical member 38, represented by the reference numerals 20' and 33'respectively, show the position of the shaft section 2i) and rollermember 38 when the belt conveying reach is heavily loaded. When the beltconveying reach is heavily loaded, a downward force is exerted on theidler roller assembly Ill. This downward force tends to pull theflexible side frame members 12 and 14 toward each other. As the flexibleside frame members 12 and 1- are drawn toward each other, the trough ofthe onveying reach 16 begins to deepen.

As the trough of the conveying reach 16 deepens, the shaft membersections 18, 2t and 22 move about the hinge pins 32 and begin to close.The resilient pads 34- come into contact with each other. When theresilient pads 34 contact each other, the inward movement of flexibleside frame members 12 and 14 is inhibited because the shaft member nowresists further closing of hinges 24.

The phantom line positions of the shaft end sections 2-9 and thecylindrical roller member 38' of FEGURES repre-' sents the relativepositions of the shaft sections and cylindrical rollers when the beltconveying reach trough is at a maximum depth. It will be appreciatedthat the embodiment of FIGURES 1-3 provides an idler roller assemblywhich has the advantages of a flexible shafted idler roller and which,at the same time, prevents the excessive troughing of the belt conveyingreach that is a major drawback of flexible shafted conveyor assemblieswhen utilized with flexible side frame supported belt conveyor systems.

When the conveyor belt is loaded under normal conditions, the flexibleside frame members 12 and 14 are maintained apart and the depth of thetrough of the conveying reach 16 may vary according to the load on theconveying reach. If the conveying reach is lightly loaded, the hingepins 32 allow hinges 24 to open to permit movement of the shaft membersections 18, 2t) and 22 to relative to each other. The cylindricalroller members 33 may then follow the belt conveying reach as it tendsto flatten. Thus, the cylindrical roller members 33 remain in contactwith the lightly loaded belt conveying reach throughout its width. Whenthe conveying reach of the belt becomes 1 excessively loaded, theflexible side frame members 12 and 14 move toward each other until theyare at a minimum distance apart. At that time the resilient pads 34 onthe ends of the individual shaft member sections contact each other andinhibit further movement of the flexible side frame members 12 and 14toward each other.

As previously stated, the resilient pads 34 are not essential featuresof the present invention. They may be dispensed with and the metal shaftmember sections may directly abut each other. The shaft member sectionswill provide a rigid member between the side frame members 12 and 14 andlimit movement of the side frame members toward each other when theconveying reach trough is extended to its maximum depth.

FIGURES 4 and show a second embodiment of the present invention.Referring to FIGURES 4 and 5, the idler roller assembly 54 extendsbetween flexible side frame members 52 and 54. The troughed conveyingreach 6 56 of an endless belt conveyor is disposed between the flexibleside frame members 52 and 54. A shaft member 58 is clamped to theflexible side frame members 52 and 54 at each of its ends by clamps 60.

In this embodiment the shaft member 53 may be formed of a flexiblematerial such as a length of wire rope or a flexible metal ribbon or thelike. The shaft member 58 supports a plurality of individual cylindricalrollers 62 as will be described. In the present instance, three rollermembers 62 are shown, however, it will be understood that a greater orfewer number of rollers may be utilized on the shaft member 58 as therequirements of the conveyor system dictate.

FIGURE 5 shows the constructional details of the individual rollermembers 62. The roller members 62 each consist of a tubular roll 64rotatably supported on shaft member 5%. Each roll 64 is supported by tworesilient annular bearing carriers ea.

In their relaxed or undistorted condition as shown at the left side ofFIGURE 5, the resilient bearing carriers 66 have a frusto conicalconcave end wall 63, a cylindrical external surface 713, a cylindricalinternal surface '72, and a frusto conical convex end wall 74. Anannular shoulder '76 is formed adjacent the cylindrical external surface76 of the bearing carrier.

Each of the resilient annular bearing carriers 6% surrounds a bearingassembly 78 which is formed with a generally cylindrical outer bearingrace $6 a generally cylindrical bearing inner race 84, and antifrictionbearing means 86 disposed therebetween. Bearing outer race 89 has anannular shoulder 82 formed thereon for a purpose to be described.

In assembling the idler roller assembly 5%, the individual rollermembers 62 are strung on the shaft member 58. A plurality of sleeves 38are used as spacer-stop members to properly position the roll-er membersas. A function of these sleeves 38 will be clarified as this descriptionproceeus.

In assembling the idler roller assembly 50, a spacer sleeve 83 is firstplaced upon the flexible shaft member 5d adjacent one end of the shaftmember S8. The sleeve 83 is secured to the shaft member 53 as by peeningor the like so that it may not be moved relative to the shaft member 58by force within the tensile strength of the shaft member 53. A rollerassembly 62 including the two annular bearing carriers 66 and thebearing assemblies '78 is then placed on the shaft member 58. When theroller member 62 is initially placed on the shaft member 58, the bearingcarriers 66 are in their relaxed condition as shown at the left ofFIGURE 5. The roller member 652 is moved along the shaft member 58 untilone of the bearing assembly inner races contacts the sleeve member 38alr ady secured to the shaft member 58. An axial force is then exertedupon the inner race 34- of the other bearing assembly to deform theresilient bearing carriers es.

An axial force of such magnitude is exerted upon the bearing that theannual bearing carrier 66 assumes the deformed shape shown at the rightof FIGURE 5. This deformed shape causes the annular bearing carrier totightly engage both the internal surface of the tubular member 64 andthe external surface of the cylindrical outer race 3! of the bearingassemblies. When both resilient bearing carriers 66 of the rollerassembly 62 have been deformed, a second sleeve member 823 is secured toshaft member 58 to maintain the roller assembly 62 in place.

When roller assembly 62 is thereby mounted upon the shaft member 58 forrotation relative to shaft member 58, a third sleeve member 88 is thensecured to the shaft member 53 at a predetermined distance from thesecond sleeve member 83. A second roller assembly is then positioned onthe shaft member 58 in abutting relation with the third sleeve member88. A compressive force is then exerted on the second roller assembly 62to deform its resilient bearing carriers 66. A fourth sleeve member 88is then secured to the shaft member'58 to retain theseca ond rollermember 62 in position. In a like manner,.the remaining roller members 62are placed upon the shaft .be described. When the idler roller assembly50 is secured to the flexible. side'frame members 52 and 54, itfunctions .as a

flexible shafted idler roller assembly. So long-asthe load on the beltconveying reachv 56 remains Within normal limits, the tension inflexible side frame members 52 and 54 maintains them spaced from eachother. The troughing ofbelt conveying reach 56 then varies With'theload, and theroller members 62 of'idler roller assembly 50 remain incontact with the underside of the conveying reach 56 throughout thewidth of the conveying reach 56. When an excessive load is placed uponthe conveying reach 56, the downward force exerted by the conveyingreach 56 draws the flexible side frame members 52 and 54- toward eachother to deepenthe' troughing of the Conveying reach 56. As the troughof conveying reach 56 deepens, the bulging protrusions 74 of theadjacent hearing carriers 66 come into contact with each other at A .30

as shown in FIGURE 4. This contact of the adjacent bearing carriers 66inhibitsfurther movement of the flexible side frame members 52 and 54toward each other; so that further deepening of the trough of conveyingreach 56 is inhibited.

V The initial distance between adjacent sleeve members-.88

on the shaft member58 determines the maximum trough depth permitted bythe idler roller assembly 50. If. the

adjacent sleeves 88 are relatively far apart, a relatively deep troughmay be formed before the bearing carriers of adjacent roller assemblies62 contact each other. On the other hand, if the sleeve members 88 areinitially placed relatively close to each other, they will permit only arelatively shallow trough before the resilient bearing carriers contacteach other and inhibit further movement of the flexible side framemembers toward each other.

FIGURES 6-8 show a third embodiment of the present invention. The idlerroller assembly 100 extends between flexible side frame members 102 and104. The troughed:

conveying reach 106 of the endless belt conveyor extends longitudinallybetween the spaced flexible side frame members.

The idler roller'assembly 100 has a shaft member 108 which is formed ofpreformed spring steel. As. shown in.

FIGURES 6-8, the shaft member 108 is spring steel of rectangularcrosssection and is formed by bending ityas at 108a, to provide theinitialtroughing effect. The use. of spring steel of rectangular crosssection for the shaft member 108 is by way of example only, the crosssectional shape of the shaft member 108 not being a critical part of thepresent invention. Any cross sectional shape of the,

. shaft member 108 is permissible. so long as the shaft member 108 hasthe requisite strength and flexing qualities.

I The shaft member 108 is secured to the flexible ,side' 7 frame members102 and 104' by clamps 110. A plurality of roller memers 112 aresupported by the shaft memberber. 1108.- -When the particular bearingassembly stands j al0ne, as when it is on the end 90f a 'roller'member112 i adjacent'the flexible side frame member 102 ort104,: an

external'bearing Washer 142 is utilized to securethe inner 114-, ismachined adjacent the end portions-of the: rollsfto create machinedinternal Mend surfaces 116.".The juncturej extending annular roll 114.

Each rollerjmember 112 is provided'with a pair 'resilof machinedendsurfaces'116'and'the natural in'ternalcylindrical surface of.tubularroll; 1143 creates inwardly; shoulders 118 at each end'oftubularient bearing carriers 120.. Resilient-'annular'bearingcare riers 120each have a frusto conical convex end wall 122;"; a frustoconicalconcave end'wall 124, azcylindrical externalsurface126, and. acylindricalinternal surface 128.

The cylindrical internal surface 128 of each, resilient: annular bearingcarrier 120.'has a portion of reduced diaineteradjacent thefrustoconical concave endwall'124' which fo'rms'an inwardlyextending annularshoulder 130 adjacent internal surface 128. p V

' Bearing assemblies 132' lare" receivedby" each of the resilientannular bearing carriers 120. The hearing assemblies .132, each have agenerally cylindrical'outer racer 134, a generally. cylindricalinnerrace i136, and antifriction means 138 ftherebetween; The outer race 134:of;

each bearing assembly'is'contig'uous to thekylindricalinternal surface128 of :theresilient bearing carrier and abuts theannular shoulder 130on surfa'ceg123, The in side diameterof eachbearing inneraracer.136is-of such size that it passes freely over shaft member 108. 5: a

Internal bearing washers 140 or external'bearing wash-i ers 142iareutilized-tosecure the bearin'ginner race to shaftmember 108 dependingupon'the location .of'the particular bearing to be secured. Internalbearing washers I 140 are, in eifect, double external washe'rs"142.:When: two bearing assemblies are inclose spaced relation to each other,'as when they are at the ends of adjacent roller members 112, a singleinternal bearing washer'140 is utilized to secure both inner races 136to the shaft memrace 136 to the shaft'mernber 108.- Each internalbearin'g washer 140. 'is. formed 'with a spherical central section 144having protruding cylindrical extensions 146. An aperture 148 isformedthrough the cylindrical extensions. and the spherical centersection; The aperture148 is of a cross-section which conforms. in shapeto t-he'crosssectio'n of shaft member 1108 as is best seen in FIGURE 8..The internalbearing'washer140-I is formed of a resilient, deformable,incompressible substance such as rubber or; the like.-

152 and the enlarged head portion 150..

The assembly of the idler. roller. of FIGURES v6-8 is: V 7 similar tothat previously describedrin connectionwwith FIGURES 4 and 5. Arollermember '112'is placed'about' the shaft memher liliis An internal-bearingWasher 140" I is then placed uponshaft 108 sothat its. cylindrical extension extends into the. cylindrical inner; race 136 of the bearingassembly. The. next adjacent idler roller-112 Iisj I then placed uponshaft -member;103 andpositioned so that its bearing ,assemblvinnerraceisforced over the cylindrical extension'xon internal bearing, :washer140; Once all the idler: roller assemblies have been positioned on shaftmembers. 108 and all of the internal bearing washers-140 are inplace,'an axial compressive force is exerted upon'the two externalbearing assemblies 132 to de- 7 form the annular bearing carriers 120 tothe: shapesshoWn-I in FIGURES 6 and "7. Ths .deformation of bearing earsriers 120 causes ftheircylindrical externalrsurface's 126'to. forcefullyengage the machined internal end surfaces 116' of the 'rolls 114; The-idef0rming force also "causes the.

bearing carrier cylindrical'intern'al surfaces;128. to force;

fully engage the outer race of bearing assemblies 132. With theresilient bearing carriers 120 properly deformed, the external bearingwashers 142 are inserted and clamped in place by securing members 156.

The components of the roller assembly 100 are so proportioned that whenthe bearing carriers 120 are properly deformed the internal bearingwashers 140 are located over the bent portion 108a of the shaft member108.

The idler roller assembly 100, when utilized with a flexible side framesupported belt conveyor, provides a roller assembly which is lessflexible than those previously described in connection with FIGURES 1-5.However, the inherent resiliency of the spring steel shaft member 108permits increased troughing of the belt conveying reach 106 when theload upon the belt is increased. The internal angle at the bent portion108a of the shaft member 108 decreases to permit the flexible side framemembers 102 and 104 to move toward each other and thereby deepen thetrough. The size and material of shaft member 108 are so selected thatthe greatest load which will be placed upon the belt conveying reach 106will not excessively trough the idler roller assembly and the movementof flexible side frame members 102 and 104 will thereby be inhibited. Inaddition to the strength of shaft member 108, the internal bearingwashers 140 serve to inhibit the movement of flexible side frame members102 and 104 toward each other once a maximum trough depth has beenreached. As may be seen in FIGURES 6 and 7, as the depth of the troughincreases and the angle of bend at 108a decreases, the spherical centersection 144 of internal bearing washer 140 becomes deformed between theadjacent bearing assemblies 132 and inhibits further bending of theshaft member 108.

From the foregoing description of the embodiments of this invention, itmay be seen that idler roller assemblies are provided which may beefficiently utilized with flexible side frame supported belt conveyors.These embodiments each provide the advantages of a flexible shaftedidler roller assembly but yet, at the same time, do not permit excessivetroughing of the belt conveying reach.

According to the provisions of the patent statutes, I have explained theprinciple, preferred construction and mode of operation of my inventionand have described what I now consider to represent its bestembodiments. However, I- desire to have it understood that, within thescope of the appended claims, the invention may be practiced otherwisethan as specifically illustrated and described.

I claim:

1. A troughing idler roller assembly comprising a shaft membertransversely spanning a pair of longitudinally extending, spacedflexible side frame members, said shaft member having end portionssecured to each of said side frame members, said shaft member beingformed of flexible material for deepening of said idler roller trough bymovement of said side frame members toward each other, a plurality ofroller members rotatably supported in end to end relation by said shaftmember and axially fixed relative to said shaft member, said rollermembers including rigid cylindrical tubes supported for rotationrelative to said shaft member by resilient, deformable bearing carriers,said bearing carriers forming end walls for said roller members, saidbearing carriers of adjacent roller members arranged to abut each otherupon movement of said side frame members toward each other to therebylimit the depth of said idler roller trough by inhibiting the movementof said side frame members toward each other at a minimum distance fromeach other.

2. A troughing idler roller assembly comprising a shaft membertransversely spanning a pair of longitudinally extending, spacedflexible side frame members, said shaft member having end portionssecured to each of said side frame members, said shaft member beingconstructed of spring steel preformed to have a plurality of straightportions connected by bent portions, said spring steel shaft memberarranged for deepening of said idler roller trough by flexing movementof said side frame members toward each other, a plurality of rollermembers rotatably supported by said shaft member, said roller membersincluding rigid cylindrical tubes supported for rotation relative tosaid shaft by resilient, deformable bearing carriers, bearingassemblies, and resilient, deformable internal and external bearingwashers, said internal bearing washers having enlarged center portionsdisposed between the bearing carriers of adjacent roller members, saidinternal bearing washers surrounding said shaft member bent portions,said bearing assemblies of adjacent roller members arranged to abut saidinternal bearing washer center portions upon movement of said side framemembers toward each other, the inherent strength and rigidity of saidspring steel shaft member and the abutting of said bearing washer centerportions by said bearing assemblies of adjacent roller members limitingthe depth of said idler roller trough by inhibiting the movement of saidside frame members toward each other at a minimum distance from eachother.

References Cited by the Examiner UNITED STATES PATENTS 2,820,541 1/ 5 8Barnish et a1. 2,942,721 6/60 Kidd et al. 2,966,255 12/60 Gleeson.

SAMUEL F. COLEMAN, Primary Examiner.

JULIUS E. WEST, ERNEST A. FALLE-R, JR.,

Examiners.

1. A TROUGHING IDLER ROLLER ASSEMBLY COMPRISING A SHAFT MEMBERTRANSVERSELY SPANNING A PAIR OF LONGITUDINALLY EXTENDING, SPACEDFLEXIBLE SIDE FRAME MEMBERS, SAID SHAFT MEMBER HAVING END PORTIONSSECURED TO EACH OF SAID SIDE FRAME MEMBERS, SAID SHAFT MEMBER BEINGFORMED OF FLEXIBLE MATERIAL FOR DEEPING OF SAID IDLER ROLLER TROUGH BYMOVEMENT OF SAID SIDE FRAME MEMBERS TOWARD EACH OTHER, A PLURALITY OFROLLER MEMBERS ROTATABLY SUPPORTED IN END TO END RELATION BY SAID SHAFTMEMBER AND AXIALLY FIXED RELATIVE TO SAID SHAFT MEMBER, SAID ROLLERMEMBERS INCLUDING RIGID CYLINDERICAL TUBES SUPPORTED FOR ROTATIONRELATIVE TO SAID SHAFT MEMBER BY RESILIENT, DEFORMABLE BEARING CARRIERS,SAID BEARING CARRIERS FORMING END WALLS FOR SAID ROLLER MEMBERS, SAIDBEARING CARRIERS OF ADJACENT ROLLER MEMBERS ARRANGED TO ABUT EACH OTHERUPON MOVEMENT OF SAID SIDE FRAME MEMBERS TOWARD EACH OTHER TO THEREBYLIMIT THE DEPTH OF SAID IDLER ROLLER TROUGH BY INHIBITING THE MOVEMENTOF SAID SIDE FRAME MEMBERS TOWARD EACH OTHER AT A MINIMUM DISTANCE FROMEACH OTHER.